In a scene towards the end of Enlightenment, one of the characters is wrapped in a sheet; one assumes the impression of a straitjacket is deliberate.

Three-quarters of the way through this production, I was feeling similarly constrained. I wasn’t being led down blind alleys or fed red herrings. Any room for speculation was blocked by some awkward dialogue. I was interested enough to want to know how the play would end, but the route to get there didn’t excite me quite enough.

This was a shame, because there was much to like about Ed Hall’s debut as artistic director of the Hampstead Theatre. The stark set, which subtly morphed from a home into a clinical examination room of hope and fear, worked well. The bombflash lighting changes were effective, and the ghostly projected images provided an opaque netherworld contrast to the characters’ attempts to rationalise their situation.

The acting too was generally good. Julie Graham, on stage for most of the play, was at her best when wracked with emotion. Richard Clothier was excellent in the role of frustrated tired husband, while Daisy Beaumont’s parasitic journalist channelled Davina McCall too closely for comfort. Tom Weston-Jones never truly convinced no matter which side of his character he was showing, but he had stage presence – essential for his scenes to be believable.

No, the production was good. It was Shelagh Stephenson’s play that I struggled with. It flitted around themes such as truth, benevolence, self-deception, hope, love, narrative and security. Yet it also found time to throw in the bourgeois decadence of capitalism, geopolitics and the nature of modern media. Highly contemporary, but perhaps a little ambitious. Worse, the philosophical musings seemed misplaced against the powerful emotional torture that was the backbone of the entire play.

The story also stretched the bounds of credibility once too often. I can turn a blind eye to some dramatic licence, but the third time around you start to lose empathy with the characters.

Stephenson’s story might be better suited to television than the stage. It needed to be faster-paced, and give more time to the evolving tension between Weston-Jones and Graham’s characters. A screenplay would be less ponderous and might do a better job of showing not telling. It might also feel less obliged to seek the laughs, which jarred at times – for this wasn’t always gallows humour. A bleaker interpretation of the script might have made the narrative more compelling without sacrificing the barbed one-liners.

Once again, the Hampstead Theatre has produced a crowd-pleaser and doubtless plenty of people will enjoy it. But for me it didn’t live up to its billing as a “mesmeric thriller”. Its strength is as a dark emotional exploration of the horror of the unknown.